In my case, after setup wizard in first boot, system hang-up with failed message:[FAILED] Failed to start oem-config.service.See "systemctl status oem-config.service" for details.Anyway, the system still can run after power-off and re-boot again.

Download Ubuntu MATE for the Raspberry Pi 2 (2015-04-22 version)

Boot-up Ubuntu MATE 15.04 for the Raspberry Pi 2 (2015-04-22 version)

To write the img on microSD, ddrescue is needed. To install ddrescue on Ubuntu, enter the command:$ sudo apt-get install gddrescue